Just be sure to have an automated top-off system..
I have an open top 20 Gallon reef with a 15 gallon refugium. I go through a
gallon every two days for top off...

Of course evap depends on MANY factors...

I find salt creep less of a problem now. I ran closed top for years because
I had an eel. That was a constant mess.
Also consider that you will need to be very careful about using aerosols and
other airborne products. My tank sits near the AC return for the apartment.
I am afraid of using any aerosols when the AC is running..

"Juan Valdez" wrote in message
...
I wanted to get your thoughts on open-top tanks...

I have a 30 gallon acrylic that I'm thinking about setting up as a
reef tank. When I say "open-top", I mean that there is very little
horizontal acrylic on the top of the tank. (There's only a "brace" in
the center.) My tank was made for a certain hood w/ integrated light
& filter that fits on top. (Imagine the top of Frankenstein's head
sitting on top pf a beautiful woman's face and body...)

The only concerns that I can think of would be excess evaporation and
the possibility of salt deposits on the "rim" of the tank. But on the
plus sude, there would be no acrylic between the lighting and the
water's surface.

Do any of you have preferences one way or the other? Does anyone have
a nice open-top reef tank like the one I'm thinking of?

Your thoughts and advice are appreciated.

Muchos Gracias,
Juan